Human papillomavirus is a favourable prognostic factor in tonsillar cancer and its oncogenic role is supported by the expression of E6 and E7

Abstract
From 1970 to 2002 in the Stockholm area, we revealed a parallel three‐fold increase in the incidence of tonsillar cancer and the proportion of human papillomavirus (HPV) positive tonsillar cancer cases, indicating a possible role of HPV infection in this disease. We have now examined whether HPV and viral load in pre‐treatment tonsillar cancer biopsies correlates to disease prognosis, and whether the presence of HPV‐16 E6 and E7 mRNA could be ascertained. The presence of HPV‐16, but not viral load, in tonsillar cancer was shown to be a favourable prognostic factor for clinical outcome. Moreover, E6 and/or E7 were expressed in almost all assessable HPV‐16 positive cases, supporting an oncogenic role of HPV‐16 in tonsillar cancer.